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' (ModeL) J. M. DODGE.

Chain.

No. 229,979. Patented July13, 1880.

,JQZNMTP HER. WASHiNGTON. D. 0.

NITED STATES PATENT OFFICE,

JAMES M. DODGE, OF NEW YORK, N. Y.

SPECIFICATION forming part of Letters Patent No. 229,979, dated July 13,1880.

Application filed June 2, 1880.

To all whom it may concern:

Be it known that I, JAMES MAPES DODGE, of New York city, in the countyof New York and State of New York, have invented certain new and usefulImprovements in Chains, (Case D and I do hereby declare that thefollowing is a full and exact description thereof, reference being hadto the accompanying drawings, making part of this specification.

In another application for Letters Patent filed by me is shown anddescribed a construction of chain-links adapted particularly to thatkind of chains composed of alternate single and double bars running inthe direction of the length of the chain, the peculiarity of whichconstruction is that the parts are so formed at the joints orarticulations that the strain and frictional wear are borne bycurvedprojections on the outer surfaces of the single bar nearits endand similar projections on the-inner faces of the double bars, and, asshownin said other application, such principle of construction may becarried out or embodied in various forms of the links; but in all formsshown the result of the invention is an improved chain of the classalluded to.

My present invention relates to that other class of chains composed of aseries of open links adapted to run on sprocket-wheels having teeth thatenter the links, and known as rag chains; and has for its object toproduce a chain of this class of such construction that the end barswill not be subjected to any serious strain or frictional wear, and sothat such strain and wear will come on curved bearingsurfaces of greatersize than it would be possible to make the hinge-like joints accordingto the heretofore practiced modes of construction; and, also, so thatthe jointed links may be readily taken apart when turned out of theirworking position, as in the case of what are known inthe art asdetachable drive-chains.

To these ends and objects, principally, my invention consists in a chaincomposed of duplicate parts, each part consisting of two side bars andone end bar, each. of said side bars being formed or provided withcurved projecting bearing-ribs located on the inner faces of said barsat one end of the link, and on the (ModeL) presently more fullydescribed, that when a series of such links are united by aninterlocking of the outer and inner projections of each link,respectively. with inner and outer projections of two adjacent links, achain will be formed in which, while the parts are free to articulateabout axes of motion substantially coincident with the axes of the endbars, and while the parts are also capable of designed detachment whenturned out of a working position, the bearing-surfaces will be muchgreater in size than it would be possible to have them according to anymode of construction in which the end bars should serve to perform thefunctions ot'journals to the joints or working points of the chain, allas will be hereinafter more fully set forth.

To enable those skilled in the art to which my invention relates to makeand use the same, I will now more particularly describe it, referring byletters to the accompanying drawings, forming part of thisspecification, in which I have illustrated a chain made according to myinvention.

Figure 1 is a top or face view. Fig. 2 is a side-edge View; Fig. 3, acentral vertical section, and Fig. 4 a central horizontal section, ofthe chain; and in the several figures the same parts will be founddesignated by the same letter of reference.

Each link is composed, as shown, of two side bars, a c,.and a connectingcross-bar, I), located near two immediately-opposite ends of the sidebars, each cross-bar b serving in the chain as an end bar to each of twoadjacent links. In other words, in a series of links forming a chain,though each link has apparently two side bars and two end bars, (ascommon to most rag-chains,) there are in reality only half as many endbars or cross-bars as there are side bars.

On the outer surfaces of the bars a a, near two immediately-oppositeends, are two curved projecting ribs or bearers, c c, and on the innersurfaces, near the other two ends of said side bars, are two curvedprojections, 61 d, between which and shoulder-like projections e c areoccasioned recesses ff, and when the parts of of the chain are united ina working condition the projections c 0 are accommodated within therecesses ff, and their convex surfaces bear on and work against theconcave surfaces of the rib-like projections d d.

The disconnected ends of the bars a a of the link have cutouts of a sortof semi-cylindrical or U-shaped contour, as clearlyillustrated at g, andthese ends of said bars, it will be noticed, are somewhat nearertogether than the opposite ends, which are connected by the cross-bar b.

This arrangement of the bars a a and this conformation of the linkpermit the disconnected ends of the side bars of each link to be placedwithin inner faces of the said bars, neartheirconnected ends,inthemannershown, with the cross bar b partially within the cutouts g, toprevent these out ends of the side bars from backing out from thebearings, and with the curved bearing-projections c c in theirrespective recesses and in engagement with the curved bearing-surfacesof the ribs d d.

At t 'i, on the inner faces of bars a, a, near where these bars areconnccted by cross-bar b, are cut-aways or depressions, such as shown,the object of which is to permit the adjacent disconnected ends of theside bars of the next link to be turned round far enough to effect anuncoupling of the links.

The necessary position of the parts for this uncoupling is illustratedat Fig. 5, where it will be seen that the link A may be moved away fromlink B in the direction of the arrow, and that but for the depressions ti, to accommodate the projections c c, the links could not have beenturned in the relative positions in which they are shown in this figure.

lhe detail shapes, proportions, and sizes of the links and their partsmay, of course, be more or less varied without departing from thedescribed principle of construction, by which, while the parts arecapable of separation when turned out of their working positions, andwhile they may turn relatively in the manner and to the extent of theusual articulated chains of the classto which my invention relates, saidparts are so jointed that at the turning-points they work with bearingsof greater superficial surface and greater strength and durability thancan possibly be attained to in detachable rag-chains such as heretoforemade and used. v

What I claim as new, and desire to secure by Letters Patent, withou trestricting my claim of invention to the precise forms of parts, is

A detachable rag-chain, composed of links each having two side piecesand one crosspiece, and having their joints or articulations composed ofcurved bearingprojections located on the outer faces of the side bars atone end and on the inner faces of said bars at the other end of eachlink, all substantially in the manner shown and described.

In testimony whereof I have hereunto set my hand this 27th day of April,1880.

B. M. SAUNDERS, ALBERT M. DAY.

